Welding and soldering are proven joining methods for metallic component parts. In an automated welding or soldering process, the component parts to be joined are fixed in a joining position and pressed against each other near the current welding or soldering point using a pressing means—for example, a pressing finger or pressing roller—during the welding or soldering, wherein the pressing means together with the welding or soldering tool travels a joining region of the component parts in the longitudinal direction of a welding or soldering seam to be produced. The component parts have to be provided in a geometry which is suited to welding or soldering. Flanges which are suited to welding or soldering are shaped on the metal sheets to be joined, for example while still being plastically reshaped in a press, or in a reshaping process subsequent to shaping in a press, such as for example edging. If the flanges are shaped while still in the press, then limits are placed on the flange geometries which can be produced, due to the need to remove the part from the mold. Edging devices for subsequently shaping the flanges are voluminous and inflexible. Furthermore, complex edging sequences can only be achieved at great cost.
Hemming also has an established role in joining metal sheets, wherein the joining combination of roll-hemming and gluing is known, which achieves a positive-fit and material-fit connection. In composites which are subjected to dynamic stresses, the glue also has the function—in addition to that of increasing the rigidity—of damping or preventing noise such as may occur, which can be generated between the joined metal sheets. The glue also fulfills a sealing function. One advantage of roll-hemming technology is its high level of flexibility with regard to the geometry of component parts. Hemming tools and methods, or more generally flanging tools and methods, are for example described in EP 1 685 915 A1, EP 1 420 908 B1, DE 100 11 954 A1 and DE 103 38 170 B4.